"This is an occasion when we have come together, both (political) parties, men and women, to reach agreement on pay equity," said Gov. Jerry Brown, who signed the bill at the Rosie the Riveter-WWII Home Front National Historical Park in Richmond.

The law, known as the Fair Pay Act, closes loopholes in existing antidiscrimination statutes that made it difficult for people to challenge their employers or prove that they were being paid at different rates due to gender. It makes it unlawful for employers to prohibit workers from discussing their own wages or the wages of co-workers -- or inquiring about another worker's wages -- if the purpose is to determine pay fairness.

"You can't challenge what you don't know," said State Sen. Hanna-Beth Jackson, D-Santa Barbara, who authored the bill, adding that the new law should be a template for other states who want to treat working women and their families fairly.

It also bars employers from retaliating against or discriminating against employees who seek out pay disparity information.

Women in California earn an average of 84 cents to every dollar a man earns, and the gap is wider for women of color, particularly Latinas, who make 44 cents to every dollar a white male counterpart makes, according to the legislation.

35 years in the making

Brown noted that in 1982 during his first go-round as governor, he signed a bill for a study of "comparable worth" between male and female workers.

Change this important "doesn't happen fast, but we're getting this done," he said.

Jackson noted that Brown first appointed her to the state Commission of the Status of Women in the late 1970s.

Asked how long it took her to build the bipartisan support for the bill, she had a quick answer: "Thirty-five years."

The bill updates and expands state fair pay standards dating back to 1949 and updated most recently in 1985. The old rules, however, allowed employers to pay different salaries based on "any bona fide factor other than sex," and only allowed pay comparisons at the "same establishment," meaning someone working for the same company in a different town could be paid differently for the same job.

Jackson's bill limits the exemptions to such things as a seniority system, a merit system or such measures as education, experience or training.

Lawsuits aren't goal

While critics have complained that the law will open the way to a flood of new pay discrimination claims, Jackson said that's not the purpose of the legislation.

"Our goal is not to end up with lots of lawsuits," she said after the signing ceremony. "Our goal is to get employers to re-evaluate how they're paying their employees."

It was no accident that Brown signed the bill at the Rosie the Riveter park, which honors the millions of women who entered the workforce during World War II, replacing men who had gone off to war.

Jackson, wearing a pink blazer to mark the day, praised the many women who have worked so long for equal pay, arguing that women and their families leave $33 billion a year on the table by not seeking pay equity.

"This is a momentous day," Jackson said. "This (law) makes for a stronger state and a stronger nation."

Only 2 dissenting votes

Jackson pushed the bill through with a unanimous vote of the state Senate and only two dissenting votes in the Assembly. She even had the backing of the California Chamber of Commerce and the Bay Area Council, business-oriented groups that seldom make common cause with many of the bill's other supporters, such as the California Labor Federation and the Consumer Attorneys of California.

"We went to the business community early and listened to their concerns," Jackson said.

While the state Chamber of Commerce originally opposed the bill, the group backed the final version of the measure.

"Equal pay for equal work, regardless of gender, should not be an issue in California," Allan Zaremberg, the chamber's president and CEO, said in a statement. The new law provides "guidance to employers to determine appropriate wages for non-gender-related reasons that allow employers to effectively manage their workforce."